Topological aspects in altermagnets have come into focus recently, and tuning the antiferromagnetic state into an altermagnetic phase remains an active frontier. We realize both within a rutile superlattice here in this paper. With first-principles calculation, we show that a uniaxial strain of only $0.5\%$ along the $c$ axis converts the ${\left({\mathrm{CrO}}_2\right)}_1/{\left({\mathrm{TaO}}_2\right)}_2$ rutile superlattice from a trivial antiferromagnet into an altermagnet with topology accompanied by a weak spin-orbit coupling (SOC). The strain opens a spin-dependent band splitting of $\sim 1.1\text{eV}$ and, despite the weak SOC together with in-plane magnetic moment orientation, generates an intrinsic anomalous Hall conductivity of order ${10}^3\text{S/cm}$, a comparable magnitude to that in ferromagnetic Weyl semimetals. Here, the Tiny SOC with an in-plane Néel orientation gaps out the Weyl nodal rings, giving rise to 16 Weyl points in the superlattice. Thus, we point out a simple route toward strain- and field-tunable, low-dissipation altermagnetic electronics.

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• Altermagnetism
• Magnetic phase transitions
• Symmetry protected topological states
• Superlattices
• Strain engineering